```html
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>数据库设计三大范式 | 数据架构设计指南</title>
    <link rel="stylesheet" href="https://cdn.staticfile.org/font-awesome/6.4.0/css/all.min.css">
    <link rel="stylesheet" href="https://cdn.staticfile.org/tailwindcss/2.2.19/tailwind.min.css">
    <link href="https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;500;600;700&family=Noto+Sans+SC:wght@300;400;500;700&display=swap" rel="stylesheet">
    <script src="https://cdn.jsdelivr.net/npm/mermaid@latest/dist/mermaid.min.js"></script>
    <style>
        body {
            font-family: 'Noto Sans SC', Tahoma, Arial, Roboto, "Droid Sans", "Helvetica Neue", "Droid Sans Fallback", "Heiti SC", "Hiragino Sans GB", Simsun, sans-serif;
            background-color: #f8fafc;
            color: #1e293b;
            line-height: 1.6;
        }
        h1, h2, h3, h4 {
            font-family: 'Noto Serif SC', serif;
            font-weight: 600;
            color: #1e293b;
        }
        .hero-gradient {
            background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
        }
        .card-hover:hover {
            transform: translateY(-5px);
            box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
        }
        .table-container {
            overflow-x: auto;
        }
        table {
            border-collapse: collapse;
            width: 100%;
            margin: 1.5rem 0;
            box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
        }
        th, td {
            padding: 0.75rem;
            text-align: left;
            border: 1px solid #e2e8f0;
        }
        th {
            background-color: #f1f5f9;
            font-weight: 600;
        }
        tr:nth-child(even) {
            background-color: #f8fafc;
        }
        .highlight-box {
            border-left: 4px solid #4f46e5;
            background-color: #eef2ff;
        }
        .code-block {
            background-color: #1e293b;
            color: #f8fafc;
            padding: 1rem;
            border-radius: 0.375rem;
            font-family: monospace;
        }
        .mermaid {
            margin: 2rem 0;
            background-color: white;
            padding: 1.5rem;
            border-radius: 0.5rem;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
        }
        .step-number {
            width: 2.5rem;
            height: 2.5rem;
            background-color: #4f46e5;
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: bold;
            margin-right: 1rem;
            flex-shrink: 0;
        }
    </style>
</head>
<body>
    <!-- Hero Section -->
    <section class="hero-gradient text-white py-20 px-4 sm:px-6 lg:px-8">
        <div class="max-w-6xl mx-auto">
            <div class="flex flex-col items-center text-center">
                <span class="inline-block px-3 py-1 text-xs font-semibold tracking-wider text-indigo-100 bg-indigo-700 rounded-full mb-4">数据库设计基础</span>
                <h1 class="text-4xl md:text-5xl font-bold mb-6">数据库设计三大范式</h1>
                <p class="text-xl md:text-2xl max-w-3xl leading-relaxed opacity-90 mb-8">
                    构建高效、无冗余数据库系统的核心原则与最佳实践
                </p>
                <div class="flex items-center space-x-4">
                    <span class="flex items-center">
                        <i class="fas fa-clock mr-2"></i>
                        <span>阅读时间: 8分钟</span>
                    </span>
                    <span class="flex items-center">
                        <i class="fas fa-layer-group mr-2"></i>
                        <span>中级难度</span>
                    </span>
                </div>
            </div>
        </div>
    </section>

    <!-- Main Content -->
    <div class="max-w-6xl mx-auto px-4 sm:px-6 lg:px-8 py-12">
        <!-- Introduction -->
        <section class="mb-16">
            <div class="bg-white rounded-xl shadow-lg p-8">
                <div class="flex items-start mb-6">
                    <div class="step-number">!</div>
                    <div>
                        <h2 class="text-2xl font-bold mb-4">为什么需要数据库范式？</h2>
                        <p class="text-slate-700 leading-relaxed">
                            数据库范式是数据库设计中的一系列规范，旨在减少数据冗余、提高数据一致性并优化数据库结构。遵循这些范式可以确保数据库的高效运行，避免数据异常，并简化数据维护工作。三大范式（1NF、2NF、3NF）构成了关系型数据库设计的理论基础。
                        </p>
                    </div>
                </div>
                
                <!-- Mermaid Diagram -->
                <div class="mermaid">
                    graph TD
                    A[数据库设计] --> B[第一范式 1NF]
                    A --> C[第二范式 2NF]
                    A --> D[第三范式 3NF]
                    B -->|确保原子性| E[消除重复组]
                    C -->|消除部分依赖| F[单列主键+完全依赖]
                    D -->|消除传递依赖| G[非主键列只依赖主键]
                </div>
            </div>
        </section>

        <!-- 1NF Section -->
        <section class="mb-16">
            <div class="flex items-center mb-8">
                <div class="step-number">1</div>
                <h2 class="text-3xl font-bold">第一范式 (1NF)</h2>
            </div>
            
            <div class="grid md:grid-cols-2 gap-8 mb-10">
                <div class="bg-white rounded-xl shadow-lg p-6 card-hover transition-all duration-300">
                    <h3 class="text-xl font-semibold mb-4 text-indigo-600 flex items-center">
                        <i class="fas fa-at